Wheat straw fibers and technology for separating films by biological enzyme method thereof

Abstract

The invention belongs to the field of bio-pulping, provides wheat straw cellulose, and aims at storing straw fibers which are subjected to directional cutting and separating by enzyme molecules and overcoming the result of damage to fine fibers in traditional chemical pulping. The wheat straw cellulose is 0.80-1.10mm in average length based on length-weight ratio and is 1.20-1.50mm in average length based on mass-weight. The invention also provides wheat straw fibers comprising the fiber structure of the abovementioned wheat straw cellulose. The quality of the wheat straw fibers meets that thebrightness (whiteness) is 53-75%; the hardness is 8-26K; the folding strength is 30-75 times; the tearing index is 3.3-5.5mN.m<2>/g; and the tensile index is 45.0-62.0N.m/g. The invention also provides a wheat straw fiber separating technology and application of the wheat straw fibers. According to the technology, high-temperature chemical boiling black liquid is not produced in the production process; the fiber quality (length, whiteness, short fiber content, etc.) is obviously superior to that of traditional chemical pulping fibers; the pulp yield is increased by more than 25% by being compared with traditional chemical pulping yield; the water consumption and the energy consumption in production are decreased by more than 30% by being compared with those in traditional chemical pulping.

Description

technical field [0001] The invention relates to a process for separating wheat straw fibers by a biological enzyme method, which belongs to the field of biological pulping. Background technique [0002] Wheat straw is mainly composed of cellulose, hemicellulose and lignin. The cellulose connected by glucose molecules accounts for about 48% of the total mass of the straw and is the most abundant component. This fiber is widely used in pulp and paper making , cellulosic ethanol, bio-dye, bio-energy and other fields. [0003] In the traditional wheat straw pulping and papermaking process, high temperature and chemical additives are generally used to separate fibers. At present, sulfite method and caustic soda anthraquinone method are mainly used. The principle of sulfite pulping is that free sulfurous acid combines with lignin to form insoluble lignosulfonic acid, and in the presence of a base, it forms easily soluble lignosulfonate, which occurs due to sulfonation In the h...

AI Technical Summary

Problems solved by technology

[0004] The characteristics of these two chemical wheat straw pulping processes are: high temperature, high pressure, and extensive use of chemical additives. In the process of delignification, not only carbohydrates (fibers) are destroyed, the pulp rate is reduced, and more serious Difficult-to-handle cooking black liquor is formed during the pulping process. Because the cooking black liquor contains a large amount of lignin and chemicals, it is an extremely difficult industrial high-concentration solid-containing waste liquid, and the existing water cannot be used. Treatment technology solves the pollution problem of cooking black liquor

[0005] At present, there are two main treatment methods for cooking black liquor from wheat straw pulping: one is the alkali recovery process, but the problem of secondary treatment of papermaking white mud has occurred in the process; the other is to concentrate the cooking black liquor and compound nutrients before spraying Pulp granulation produces lignin fulvic acid fertilizer, but VOCs and NH are produced due to high temperature drying process in spray granulation 3 The foul smelling smoke causes secondary pollution. At present, there is no reasonable way to treat the black liquor of wheat straw pulping and cooking. The development of a new green separation process of wheat straw fiber is the goal pursued by researchers and production enterprises.

Images